The hip joint is surrounded by very strong ligaments and muscles, and the posterior dislocation of the joint can only occur under the effect of very heavy violence, and the common complications are as follows: 1. the dislocation is accompanied by a fracture of the acetabulum. 2. the dislocation is accompanied by obvious misalignment, which can lead to damage to the sciatic nerve. 3. because of the strong effect of violence, femoral head necrosis is easily formed in the late stage of dislocation. 4. After dislocation because of the need for long time bed rest, older patients may have venous thrombosis of the lower limbs. Therefore, after having a posterior dislocation of the hip joint, you should actively go to the hospital to reset the dislocation as soon as possible, and cooperate with the corresponding follow-up treatment to avoid these complications as much as possible. For example, if there is a fracture, whether early surgical fixation is needed after correction of the dislocation, or whether early neurotrophic treatment is needed for sciatic nerve injury.